Presently, ball retainers are stamped on low-speed multi-positional presses. As many as five or six, or even more, operations are needed to stamp a properly functioning ball retainer. In such presses, first a ring is cut out of the metal band. Then, in separate operations, the ring is stamped into a ball retainer. Naturally, each operation has a margin of error. Thus, after several operations a considerable margin of error is built up. Therefore, it proves to be extremely difficult to manufacture a ball retainer within high tolerances.
Additionally, the shape of the spherical seats for the ball does not always conform to the contour of the ball. This causes the ball to move within its seat and to generate rattling noises. In addition to the noise being unacceptable, the rattling decreases the service life of the ball retainer. The repeated rattling causes the ball retainer and the bearing to wear out much too quickly.